Post hole punch



April 18, 1939. E. DAHL POST,HOLE PUNCH '2 Sheets-Sheet 1 Filed Feb. 21, 1958 INVENTOR. [ow/N 04/7 4 BY W ATTORNEY.

E. DAHL April 18, 1939.

POST HOLE PUNCH Filed Feb. 21, 1938 2 Sheets-Sheet 2 a" n vw I INVENTOR. f0 W/N 5/4/94 aa? 5 ATTORNEY.

Patented Apr. 18, 1939 UNITED STATES PATENT OFFICE 2,154,732 POs'r HOLE PUNCH Dahl, Denver, 0010.

Application February 21, 1938, Serial No. 191,596

This machine is not to be confused with pile drivers which drive a form into the ground by striking blows thereon, for in this machine the In entire hole forming element is continuously raised and dropped into the ground during the punching operation, no separate hole forming devices are employed. It has proven exceedingly valuable for setting guardrail posts on it mountain roads where the large quantity of rock makes digging an expensive proceeding.

Other objects of the invention are to provide a hole driver or punch which will. break and crush any rock encountered in the hole; which 20 will be adjustable asto angle so that the hole will be vertical regardless of the incline of the surrounding terrain; which will require but a.

drawings which form a part hereof. Like numer- 35 als refer to like parts in all views of the drawings and throughout the description.

In the drawings:

Fig. 1 is a perspective view illustrating the device as it would appear in use.

Fig. 2 is an enlarged horizontal section taken on the line 2-2, Fig. 3.

Fig. 3 is a vertical section through the device.

Fig. 4 is a plan view of the invention with the upper bracket broken away.

In the drawings a typical caterpillar tractor is indicated at III. This invention is particularly designed to be applied to this type of tractor, although it is not limited to this particular use. Tractors of this type are provided with cable winch drums such as shown at 3 I.

Tractors of this type are provided with a horizontal draw bar plate Ii supported upon projecting beams 12. The invention may be ata tached to the draw bar plate I l or, if desired, may

5 Claims. (01. 255-1) be attached to a separate plate which in turn is attached to the draw bar plate H.

The post hole punch comprises a vertical frame l3 hinged to a pair of angle feet I upon suitable hinge bolts IS. The frame I3 is supported in its 5 upright position by means of adjustable brace members It. The brace members preferably v comprise tubular sections for telescopically engaging rods I! which are attached to. the forward portion of the tractor in any desired manner. These members are formed with a seriesof pin openings l8 by means of which'the length of the entire brace member may be adjusted.

A V-shaped brace frame I! is projected from the draw bar beams l2 to support a base plate 20. lo

The base plate contains an opening for receiving a punch guide tube 2!. The punch guide tube contains a series of projecgons or bosses 22 which are formed by welding a gob of iron thereon. The bosses 22 prevent the tube 2i from 20 slipping through the base plate 20, and provide a universal joint support for the tube2l, a pair of brace frames 23 and 24 extending from the frame I3 about the tube. In one of these frames, a pair of crank jack screws 25 is mounted which 25 act to clamp pads 26 against the tube 2|. By tightening one of these screws and loosening the other, the vertical angle of the tube 2| may be varied.

The tube 2| is designed for guiding a heavy, solid iron punch 21, the lower extremity of which is pointed as shown at 28. The punch is raised in the tube through the medium of a cable 29 which returns over a pair of sheave wheels II to the cable drum 3| of the tractor. The sheave wheels 30 are mounted in a swinging bracket 32 Operation The operator drives the tractor to position the tube 2| over the desired place for the hole. He then elevates the punch 21 to the top of the tube and releases the winch clutch of the tractor to allow the punch to drop. These punches weigh approximately three thousand pounds and upon release of the clutch, the punch falls guided by the tube striking the ground to depress or punch a hole therein. The punch is elevated and dropped the number of times necessary to produce a hole of the desired depth. In ordinary ground, two drops of the punch produces a hole 56 approximately four feet deep. In rocky ground additional drops will be roiplacing the guardrail holes along mountain gradient will be vertical without further adjustments. In some cases it is necessary that the tractor be placed longitudinally of the road. In these cases, the brace members It are adjusted so that the tube will be vertical as the tractor inclines.

It has been found advantageous to provide a small window or opening 34 in the tube by means of which the operator can determine the depth of the hole. when the top of the punch appears opposite the window, the hole has reached the desired depth.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention.

' Having thus described the invention, what is claimed and desired secured by Letters Patent is:

1. A post hole punch attachment for tractors comprising: a vertical frame; means for attaching said frame to a tractor; a vertically positioned tube supported by said frame; a heavy pointed punch member adapted to be dropped within said tube; and means for elevating said punch member within said tube.

2. A post hole punch attachment for tractors comprising: a vertical frame; means for attaching said frame to a tractor; a vertically positioned tube supported by said frame; a heavy pointed punch member adapted to be dr pped within said tube; means for elevating said punch member within said tube: and means for varying the vertical angle of said tube within said frame.

sass-res 3. A post hole pimch attachment for tractors comprising: a vertical frame; means for attaching said frame to a tractor; a vertically positioned tube supported by said frame; a heavy pointed punch member adapted to be dropped within said tube; means for elevating said punch member within said tube; means-for varying the vertical angle of said tube within said frame; and means for varying the vertical angle of said frame on said tractor.

4. A post hole punch attachment for tractors comprising: a vertical frame; means for hinging thelower extremity of said-frame to said tractor; brace arms supporting said frame from said tractor; a supporting member extending from said frame; a tube supported by said member; means for maintaining said tube vertical; an elongated, heavy. pointed punch member slidably mounted in said tube; a bracket extending over said tube; sheave wheels carried by said bracket; and a cable extending from said punch member over said sheave wheels to the hoisting mechanism of said tractor so that saidpunch may be raised and dropped within said tube, so as to enter the ground when dropped. 7

5. A post hole punch attachment for tractors comprising: a vertical frame; means for biasing the lower extremity of said frame to said tractor; brace armssupporting said frame from said tractor; a supporting member extending from said "frame; a tube supported by said member; means for maintaining said tube vertical? an elongated. heavy, pointed punchmember slidably mounted in said tube; a bracket extending over said tube;

sheave wheels carried by said bracket; and a cable extending from said punch member over said sheave wheels to the hoisting mechanism of said tractor so that said punch mayfbe'raised and dropped within said tube, so as to enter the ground when dropped; and said bracket being hinged to said frame so, that it may swing with the varying .angles of said tube.

EDWIN DAI-IL. 

